This invention relates generally to methods and apparatus for analysis of vessel images, and more particularly to methods and apparatus for assisting medical care personnel such as radiologists in preparing measurements and reports during radiological examinations from images derived from computed tomographic, MR, and 3D radiation imaging.
In at least some computed tomography (CT) imaging system configurations, an x-ray source projects a fan-shaped beam which is collimated to lie within an X-Y plane of a Cartesian coordinate system and generally referred to as the xe2x80x9cimaging planexe2x80x9d. The x-ray beam passes through the object being imaged, such as a patient. The beam, after being attenuated by the object, impinges upon an array of radiation detectors. The intensity of the attenuated beam radiation received at the detector array is dependent upon the attenuation of the x-ray beam by the object. Each detector element of the array produces a separate electrical signal that is a measurement of the beam attenuation at the detector location. The attenuation measurements from all the detectors are acquired separately to produce a transmission profile.
In known third generation CT systems, the x-ray source and the detector array are rotated with a gantry within the imaging plane and around the object to be imaged so that the angle at which the x-ray beam intersects the object constantly changes. X-ray sources typically include x-ray tubes, which emit the x-ray beam at a focal spot. X-ray detectors typically include a collimator for collimating x-ray beams received at the detector, a scintillator adjacent the collimator, and photodetectors adjacent the scintillator.
One application of computed tomographic (CT) imaging, as well as magnetic resonance (MR) imaging and 3-D x-ray imaging (3DXR), is vascular analysis. X-ray quantification and analysis of vessel pathologies are important for radiologists who are called upon to assess stenosis or aneurysm parameters, quantify lengths, section sizes, angles, and related parameters. In some known imaging systems, analysis of vessel pathologies using three-dimensional data, such as CT, MR or 3DXR.
Analysis of visual pathologies may sometimes be difficult since the operator has to track possibly tortuous structures. These imaging systems may include a method whereby a path is located between a starting point and an ending point, then the operator navigates along the calculated path with the aid of simple interface devices, such as sliders or scrollbars which may increase the computer time required to define and calculate the paths. Further, in the case of occlusions or discontinuous paths additional steps may be required to view the structure.
In one embodiment, a method for analyzing a tubular structure in a patient is provided. The method includes receiving a cursor first position within a displayed tubular structure representative of the tubular structure in the patient, determining a path inside the tubular structure based only on the received cursor first position, and moving a cursor along the path by a pre-determined distance in a pre-determined direction to a cursor second position.
In another embodiment, a method for reviewing a tubular structure over a passage of time is provided. The method includes providing at least a first three-dimensional data set at a first time and a second three-dimensional data set at a second time representative of the same tubular structure, generating a first view of the first three-dimensional data set and a second view of the second three-dimensional data set, and positioning a first cursor at a first three-dimensional location within the first view and positioning a second cursor at a first three-dimensional location within the second view corresponding to the first cursor location in the first view. The method also includes determining a path inside the tubular structure, defining a direction from the cursor position in at least one of the first view and the second view, and moving the first cursor along the determined path by a pre-determined distance in a pre-determined direction to first cursor second position and moving the second cursor along the determined path by a pre-determined distance in a pre-determined direction to second cursor second position.
In a further embodiment, a computer readable medium encoded with a program executable by a computer for analyzing a tubular structure in a patient is provided. The program is configured to instruct the computer to receive a cursor first position within a displayed tubular structure representative of a tubular structure in a patient, determine a path inside the tubular structure based on the received cursor first position, wherein the determined path includes a determined endpoint, and move a cursor along the path by a pre-determined distance in a pre-determined direction to a cursor second position.
In yet another embodiment, a medical imaging system for analyzing a tubular structure in a patient is provided. The medical imaging system includes a detector array, at least one radiation source, and a computer coupled to the detector array and radiation source. The computer is configured to receive a cursor first position within a displayed tubular structure representative of the tubular structure in the patient, determine a path including an endpoint inside the tubular structure based on the received cursor first position, and move a cursor along the path by a pre-determined distance in a pre-determined direction to a cursor second position.